Too Much Too Soon song meaning

The song describes 2 people - a girl and a guy. The girl is living her life at a very high speed, she always needs more and it's still never enough. Whereas the guy is always complaining about how it was better before and is living his life in anticipation of an end. They both don't know when to stop and reconsider, so they're taking it "too much too soon" and when it's too late to look back, their lives suck and they can't change anything now.

Since Too Much Too Soon is an American Idiot outtake, it is possible that the characters in this song are Jimmy/JOS and Whatsername - she's the one who's "always living like she's running out of time", and he's the one who's living in the past. It is indeed possible since Whatsername is really someone who's always running and always wants more. Jesus is never satisfied, always thinks something is wrong and maybe before was better than now. In the end they both lose.

It's also possible that the male character in this song is an image of George W. Bush, who always tries to force his outdated views on everyone. "So God bless your fucking past and to hell with your glory" - he wants to change the world to something he considers right, and without realizing that he might be wrong he's taking it "too much too soon".